// SPDX-License-Identifier: AGPL-3.0-only
/**
* Digital Voice Modem - Audio Bridge
* AGPLv3 Open Source. Use is subject to license terms.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* @package DVM / Audio Bridge
* @license AGPLv3 License (https://opensource.org/licenses/AGPL-3.0)
*
*   Copyright (C) 2022-2024 Bryan Biedenkapp, N2PLL
*
*/

using fnecore.DMR;
using fnecore;

using NAudio.Wave;

namespace DVMConsole
{
    /// <summary>
    /// Implements a FNE system base.
    /// </summary>
    public abstract partial class FneSystemBase : fnecore.FneSystemBase
    {
        public const int AMBE_BUF_LEN = 9;
        public const int DMR_AMBE_LENGTH_BYTES = 27;
        public const int AMBE_PER_SLOT = 3;

        public const int P25_FIXED_SLOT = 2;

        public const int SAMPLE_RATE = 8000;
        public const int BITS_PER_SECOND = 16;

        public const int MBE_SAMPLES_LENGTH = 160;

        public const int AUDIO_BUFFER_MS = 20;
        public const int AUDIO_NO_BUFFERS = 2;
        public const int AFSK_AUDIO_BUFFER_MS = 60;
        public const int AFSK_AUDIO_NO_BUFFERS = 4;

        public new const int DMR_PACKET_SIZE = 55;
        public new const int DMR_FRAME_LENGTH_BYTES = 33;

        /*
        ** Methods
        */

        /// <summary>
        /// Callback used to validate incoming DMR data.
        /// </summary>
        /// <param name="peerId">Peer ID</param>
        /// <param name="srcId">Source Address</param>
        /// <param name="dstId">Destination Address</param>
        /// <param name="slot">Slot Number</param>
        /// <param name="callType">Call Type (Group or Private)</param>
        /// <param name="frameType">Frame Type</param>
        /// <param name="dataType">DMR Data Type</param>
        /// <param name="streamId">Stream ID</param>
        /// <param name="message">Raw message data</param>
        /// <returns>True, if data stream is valid, otherwise false.</returns>
        protected override bool DMRDataValidate(uint peerId, uint srcId, uint dstId, byte slot, fnecore.CallType callType, FrameType frameType, DMRDataType dataType, uint streamId, byte[] message)
        {
            return true;
        }

        /// <summary>
        /// Creates an DMR frame message.
        /// </summary>
        /// <param name="data"></param>
        /// <param name="srcId"></param>
        /// <param name="dstId"></param>
        /// <param name="slot"></param>
        /// <param name="frameType"></param>
        /// <param name="seqNo"></param>
        /// <param name="n"></param>
        public void CreateDMRMessage(ref byte[] data, uint srcId, uint dstId, byte slot, FrameType frameType, byte seqNo, byte n)
        {
            RemoteCallData callData = new RemoteCallData()
            {
                SrcId = srcId,
                DstId = dstId,
                FrameType = frameType,
                Slot = slot,
            };

            CreateDMRMessage(ref data, callData, seqNo, n);
        }

        /// <summary>
        /// Helper to send a DMR terminator with LC message.
        /// </summary>
        public void SendDMRTerminator(uint srcId, uint dstId, byte slot, int dmrSeqNo, byte dmrN, EmbeddedData embeddedData)
        {
            RemoteCallData callData = new RemoteCallData()
            {
                SrcId = srcId,
                DstId = dstId,
                FrameType = FrameType.DATA_SYNC,
                Slot = slot
            };

            SendDMRTerminator(callData, ref dmrSeqNo, ref dmrN, embeddedData);
        }

        /// <summary>
        /// Event handler used to process incoming DMR data.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected override void DMRDataReceived(object sender, DMRDataReceivedEvent e)
        {
            return;
        }
    } // public abstract partial class FneSystemBase : fnecore.FneSystemBase
}